Remove comments from javascript

Signed-off-by: Raimund Schlüßler <raimund.schluessler@mailbox.org>

package.json

@@ -82,6 +82,7 @@
 		"stylelint-scss": "^3.10.0",
 		"stylelint-webpack-plugin": "^0.10.5",
 		"svg-sprite": "^1.5.0",
+		"terser-webpack-plugin": "^1.4.1",
 		"vue-click-outside": "^1.0.7",
 		"vue-jest": "^3.0.4",
 		"vue-loader": "^15.7.1",

webpack.prod.js

@@ -1,7 +1,18 @@
 const merge = require('webpack-merge')
 const common = require('./webpack.common.js')
+const TerserPlugin = require('terser-webpack-plugin')
 
 module.exports = merge(common, {
 	mode: 'production',
-	devtool: '#source-map'
+	devtool: '#source-map',
+	optimization: {
+		minimizer: [new TerserPlugin({
+			terserOptions: {
+				output: {
+					comments: false,
+				}
+			},
+			sourceMap: true,
+		})],
+	}
 });